1. Field of the Invention
My present invention relates to archery bows, and more particularly to cross-coupled archery bows, i.e., archery bows comprising cross-coupling or draw force transfer cables by means of which draw forces are transferred between opposing limbs.
2. Description of the Prior Art
Cross-coupled archery bows are well known in the prior art.
Holless W. Allen U.S. Pat. No. 3,486,495, issued on Dec. 30, 1969, discloses archery bows with draw force multiplying attachments. More particularly, Allen discloses archery bows having rotatable, variable leverage pulley members on the tips of the bow limbs. A cross-coupling cable is wound around the pulley members to provide mechanical advantage, and less force is required to pull the bow string in a fully drawn position than to hold the bow string at an intermediate draw position.
Arthur J. Frydenlund U.S. Pat. No. 3,967,609, issued on Jul. 6, 1976, discloses a cross-coupled archery bow which is provided with a concentric sheave at each of the bow limb tips, and has a pivotable lever with a pulley mounted at each end of the bow handle. The levers are connected via a continuous stretch reeved over each lever and extending toward the most remote sheaves on the bow limbs and then to the ends of the bow string. A tensioning cable of fixed length is connected between each lever and its respective nearby or adjacent sheave. As the bow string is drawn the draw force will vary due to the pivoting of the levers. When the levers pass over dead center the tension cable will engage a member on each lever and limit the maximum draw of the bow string.
Jim Zenji Nishioka U.S. Pat. No. 3,989,026, issued on Nov. 2, 1976, discloses an archery bow with balanced adjustable tension having a pair of oppositely extending bow arms on a main body portion having guides on their tips. A bow string extension between the tips has end sections movably contacting the guides. The bow has a drawing force produced either by flexible bow arms or a resilient member on the bow, and a second guide is employed to receive the end sections of the bow string and position them so that they will be acted upon equally by the drawing force while moving in unison with it to provide a balanced bow for accurate shooting of arrows.
Gary Simonds and Arnold D. McKee U.S. Pat. No. 4,368,718, issued on Jan. 18, 1993, discloses a compound bow having an eccentric cam member pivotably mounted on each bow limb tip, each cam including an outwardly projecting hook or lever section; the ends of said bowstring being wrapped around said cams.
David W. Jarrett U.S. Pat. No. 4,512,326, issued on Apr. 23, 1985, discloses an archery bow including oppositely extending rigid limbs each rotatably supporting lever mechanisms. A pair of flexible limbs are secured to the bow overlying the respective rigid limbs. A bow string is connected to each of the lever mechanisms. Also a separate force cable is connected between each terminal end of the flexible limbs and respective lever mechanisms. The lever mechanisms each are provided with a stop limiting rotation thereby preventing an over-center condition. The lever mechanisms include pulleys receiving a synchronizing cable evenly distributing pull forces on the bow string to the ends of the rigid limbs. The bow string connections, the force cable connections and the lever mechanism pivot points are placed to provide a second class lever mechanical advantage. Rotation of the lever mechanisms to place the cable connecting points and the lever mechanisms pivot points in a near straight position reduces the shooting-hold force to near zero. The magnitude of the shooting-hold force is variably regulated by adjustment of the stop.
These prior art cross-coupled archery bows are characterized by one or more of the following disadvantages: mechanical complexity, heavy bow weight, lack of full adjustability, friction drag due to the utilization of pulleys which rotate through large angles, i.e., angles approaching 90.degree. or more, reaction against the hands of the archer due to abrupt movement of the bow resulting from abrupt acceleration or halting of moving parts, unadjustable imbalance between the upper and lower halves of the bow resulting in non-linear arrow flight, etc.
It is believed that the United States patents listed immediately below contain information which is or might be construed to be material of the examination hereof.
U.S. Pat. No. 3,851,638
U.S. Pat. No. 4,667,649
U.S. Pat. No. 4,672,943
U.S. Pat. No. 4,683,865
A copy of each of the above-cited United States patents was supplied to the United States Patent and Trademark Office at the time of filing.
No representation or admission is made that any of the above-cited United States patents is part of the prior art, or that a search has been made, or that no more pertinent information exists.
The term "prior art" as used herein or in any statement made by or on behalf of applicant means only that any document or thing referred to as prior art bears, directly or inferentially, a date which is earlier than the effective filing date hereof.